Instrument pointer actuating mechanism and adjustment



I1-me 23, 1953 H..HERMANNY 2,642,743

INSTRUMENT POINTER ACTUATING MECHANISM AND ADJUSTMENT Filed March 18,1947 l 4 Sheets-Sheet l I N Y l ,s P TO I\\ SGUND-l o l l TANK F /A'Ill/lll H. HERMANNY June 23, 1953 INSTRUMENT POINTER ACTUATING MEHANISMAND ADJUSTMENT Filed March 18, 1947 4 sheets-sheetl 2 INVENTOR.

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H. HERMANNY June 23, 1953 INSTRUMENT POINTER ACTUATING MECHANISM ANDADJUSTMENT Filed March 18, 1947 4 Sheets-Sheet 3 INVENToR. /f/A/R/cf/f/mMA/v/W ATTORNEY June 23, 1953 H. HERMANNY I 2,642,743

INSTRUMENT POINTER ACTUATING MECHANISM AND ADJUSTMENT Filed March 18,1947 I 4 Sheets-Sheet 4 I J5 C30 //41 ff /V IN VEN TOR. /fE/NR/CH H/SHMANNY 'F11-.75 l2:4.-.7'2 7 17 BY www ATTORNEY Patented June 23, 1953INSTRUMENT POINTER ACTUATING MECH- ANISM AND ADJUSTMENT HeinrichHermannyj Valley Stream, N.v Y. Application March 18, 1947, Serial No.735,331

This invention relates to instruments, gaugesA and the like andparticularly to pointer actuation linkages and adjustments for such.

The invention will be particularly described in its preferredembodiments as applied to pressure gauges of the hydrostatic type, butit will be understood that the novel subcombination linkages andadjustments are capable of use ink other gauges and instruments.`

, The invention in its preferred embodiment is peculiarly adaptable tomeasuring the depth of fuel in tanks such as motor boat fuel tanks andhome fuel oil tanks. It contains a source of pressure 'Which is manuallyactivated to actuatea pressure responsive element connected to a pointerby a simple loW friction linkage containing both zero and rateadjustments that enable the gauge to be speedily calibrated to coactwith its associated tank.

While hydrostatic fuel gaugeshaving rate adjustments are known, suchgauges which are commercially used Within my knowledge are relativelycomplicated as compared to my construction and the mechanisms cf theirrate adjustments introduce additional sliding friction losses that areobjectionable from the standpoint of accuracy and sensitivity, and myconstruction avoids this objection.

With the above in mind it is a major object of the invention to providea novel instrument pointer actuating linkage and adjustment.

A further object oi the invention is to provide 13 claims. (c1. '7s-41o)a gauge construction embodying a pivoted linkage interposedA betweena'pressure sensitive element and a pointer, the linkage ccntaininganovel fulcruin adjustment. y

A further object of this invention is to provide a gauge of theabove-mentioned character also having a novel zero adjustment.

It is a further object of the invention to provide a novel pointeractuating linkage and adjustment.

A further object of the invention is to provide Figure 1 is a frontelevation of the gauge of Figure 2;` e, Figure 2 is a section inelevation illustrating a gauge according'to a preferred embodiment ofthe invention connected to the top of a fuel tank;

Figure 3 is a section on line 3-3 of Figure 2 illustrating details ofthe pointer linkage mounting and the rate adjustment of the pointer;

Figure 4 is a rather diagrammatic pseudo-,perspective view illustratingfurther the pointer linkage and adjustment;

Figure 5 is a side elevation of the eccentric rocker of the adjustment;

Figures 6 and 7 are opposite end views of the rocker of Figure 5;

Figure 8 and 9 are sections respectively on lines 8-8 and 9-9 of Figure5;.

Figure 10 is an axial section through therelatively adjustable endsupport for the rocker;

Figure l'l is an inner end View of the support of Figure 10;` y 'lFigure 12 is afront view of a gauge according to a further embodiment ofthe invention;

Figure 13 is a front elevation with the outer case removed and partly insection through the gauge of Figure 12 illustrating the pointer linkage;

Figure 14 is a side elevation partly in section through the gauge ofFigure 12 and showingits connection to the bottom of a fuel tank;

Figure 15 is a diagrammatic pseudo-perspective view of the ypointeractuating linkage and rate adjustment of the gauge of Figures 12-14;

and f Figures 16, 17, 18 and 19 are top, side'and opposite end viewsrespectively of the eccentric adjustment rocker of the gauge of Figures12-15.

In the embodiment of Figures 1-11, a hydro-- static pressure gauge 20 isconnected by a conduit 2| to a fuel tank 22 in a motor boat, althoughthe bottom connection of Figure 14 could be employed Where spaceconsiderations demand. Gauge `2l comprises a rigid front case member 24having a peripheral iiange 30 secured asby rivets 25 in an opening in aninstrument panel 26. vCase member 24 houses an index dial 2lapertured'at 28 and containing a scale 29 here indicating the depth offuel in tank 22.

` Dial 21 is held flat `against a rear case member 3| by a spacer collar32, a transparent glass Window 33 and a split ring and groove assemblyat 34. internal shoulder 35 in case member 24 so that ring 34 holds casemembers 24 and 3| tightly together in the assembly, and a pin 36 Orientsthe mechanism on rear case member 3| with respect to the front casemember 24. A sheet metal rear Case member 3| is seated at the bottom ofotally mounted upon the upper end of a cradle 42 that in turn ispivotally mounted ontherear end of a cylinder 43 projecting integrallyrear# wardly from case member 3|. Cover 31 is secured on the rear casemember .as by a screw 4D.

Cylinder 43 contains a chamber 4.4 open at its front end where it iscovered by dial 21 in the aS- sembly. A fluid tight leather cup typepiston 45 d is reciprocably mounted in chamber 44 manually actuated by arod 46 that passes through an `aperture in dial 21 and a rubber grommet.41 in an aperture in window 33. Y A knob 48 is secured toY rod 46 as bya set screw 49 so that the knob may be removed to disassemble thegauge.l A suitable eyelet 5| rigid with dial 21 serves as a piston rodguide and support and also to center a coiled compression spring 52 thatreacts in the assembly between the relatively stationary dial 21 and themovable piston 45, so that piston 45 `is normally urged to the positionof Figure 2. An air admission aperture 50 is provided in the wall ofchamber 44 for a purpose to be described.

The integral rear end of cylinder 43 closes chamber 44 except for asmall diameter axial bore 53 that places piston chamber k44 in fluidcommunication with an outlet pressure chamber 54 havingr its outer endthreadedto. receive a tting 55 on the end of conduit2 ,The rear Wall ofpiston chamber 44 carries a washer 58 of synthetic rubber or likeresilient material apertured in alignment with bore 53and adaptedto betightly engaged and compressed by the annular` crowned rear end ofpiston 45 to sealingly close communication between chambers 44 and 54when the piston is spring urged into its position of Figure 2. Piston 45carries a leather cup 51 secured to it by a Washer 58 engaged by therear end of spring 52 whereby the chamber sections 44 at opposite sidesof piston 45 are'uid tight with respect to each other. Piston 45 eiectsair tight closure of bore 53 in Figure 2.

The interior of a Sylphon or pressure sensitive.l bellows 59 issubjected to the fluid pressure of outlet chamber 54 by a conduit 6|.Sylphon 59 at one end has a support projection 62 adjustably secured inan aperture in rear case member 3| as by set screw 63. The rear end ofSylphon 59 is pivotally connected to a link 64 that in turn is pivotallyconnected to rocker 4 Referring now to Figure 3, cradle 42 comprises apair of upright arms 65 and 68 integrally connected at their upperendsby a llat bridge 61. The lower ends of arms 65 and 66 are journalled atopposite sides of cylinder 43 on a cylindrical transverse shaft 68.whichextends through an aperture in the solid rear end of cylinder 43 and isheld against rotation or sliding as by set screw 69. If desired thepivots for cradle 42 could be integral or otherwise rigid projectionsfrom cylinder 43 or pivot pins extending into apertures in cylinder 43.

Cradle 42 is biased clockwise in Figure 2 by a tension spring 1| coiledabout shaft 38 with one end hooked over the front of cradle arm 65 andthe opposite end anchored on cylinder 43.

Clockwise movement of cradle 42 is opposed by an adjustable set screw 12mounted in a recessed boss 13' in an integral extension of cylinder 43and bearing against bridge 61. When screw T2 is rotated clockwise itmoves forwardly to rock cradle 42 counter-clockwise against the tensionof spring 1| toward Sylphon 59. As will further appear, during thisadjustment the pivot 82' (Figure 3) between link 64 and the rockerassembly 4| serves as a stationary fulcrum about which rocker assembly4| rotates to thereby move the vpointer end 39 upward (Figure 1) onscale 29. Reverse rotation of screw 12 permits clockwise movement ofcradle 42 away from Sylphon 59 under-:the inuence of spring 1I to lowerpointer en d 39 with respect to scale 29.

Screw 12 thus provides a zero adjustment for pointer 38jwhich isindependent of the fulcrum adjustment at rocker assembly 4| to bedescribed below. This zero adjustment is made with the tank empty uponinstallation, or at anytime when Sylphon 59 is relaxed with atmosphericpressure within and without.

Referring to Figures 3-11, rocker assembly 4| is made up of tworelatively adjustable and eccentrically mounted parts consisting of arocker bar 13 (Figures 5-9) and a support block 14 (Figures 10 and ll).Rocker bar 13 is primarily of of square cross section as illustrated inFigures 6 and 7 with a short central cylindrical axial bore 15 at oneend and a recessed flat shoulder 15 extending to its other end. Theplane of shoulder 16 is parallel to the axis of bore 15 and thehorizontal diagonal across the bar as illustrated in Figures '1 and 8.

The rear end of pointer 38 is rounded to extend snugly through a hole 11drilled normal to shoulder 13 and is staked over at 18 (Figure 4) tosecure it rigidly to rocker bar 13.

Beyond the bottom of bore 15, rocker bar 13 is formed with a deeptransverse notch bottoming in a atface 19. A small hole is drilledthrough the bottom of bore 15 parallel and eccentric to the axis of bore15 so that a small diameter pivot pin 82' (Figure 3) for the rear end oflink 64 may be inserted through bore 15 and tted into hole 89 below thebottom of bore 15. The width and depth of the notch at 19 provide forfree pivotal movement of link 84. The eccentricity of bore 15 and pin 82determines the adjustment range.

Opposite bore 15, rocker bore 13 is formed with a recess having aconical bearing surface 8| coaxial with bore 15. Surface 8| is adaptedto seaton the conical tip 82 of a screw pivot 83 (Figure 3) mounted onthe upper end of cradle wall 56.

The other end of rocker bar 13 has bore 15 telescoped upon a cylindricalboss 84 projecting from non-circular block 85. The other end of block 85is formed with a conical bearing surface 86 having its axis parallel tothe axis of boss 84 but eccentric with respect to it. A screw pivot 81axially aligned with screw pivot 83 and having a conical tip 88 ttingwith surface 86 supports that end of the rocker assembly. Bearingsurfaces 8| and 8B are of slightly greater angle than the correspondingconical ends of pivots 83 and 81 for a purpose to appear.

The t of boss 84 in bore 15 is a snug friction nt such that the rockerassembly of bar 13 and support 14 normally rotates as a unit aboutaxially aligned pivots 83 and 81 under inuence of Sylphon 58.

In the instrument, rocker assembly 4| is supported at opposite ends byaxially aligned pivots 83 and 81, but the longitudinal laxisof therocker 4|, and with it the axis of pin 82',` is usually at a slightangle to the alignedv pivot axes due to the eccentricity of boss 84. Theaxis of rotation of rocker 4|, which is the aligned pivot axis, changesposition with respect to the axis' of pivot 82 during the adjustmenteffected liquid head is balanced and the pressure becomes constant thepointer becomes stationary a by relatively rotating bar 13 and block 14thusy block14, as with Wrenches'andas permitted'byA the friction t ofboss 84 and recess l'15, the fulcrum axis of the rocker assemblyl 4| maybe shifted and the effectiveleverage distance be' tween pvot 82 and thefulcrum axis of the rocker assembly may bechanged, thereby changing Vtheamount that thel pointer 38 -is moved during a given longitudinaldisplacement of link 64. The variation of thefmotion magnification ofVthe linkage is an adjustment'of the V,rate of pointer deflection whichenables the gauge to be adapted to accurately coact with an associatedfuel tank.

As illustrated in Figure 2, the tank end of conduit 2| is coupled by asuitablek fitting Afili with a vertical tube 9| that is open at 92 nearthe bottom, of the tank, so as to providegfluid `com` munication betweenchamber 54v and opening92.`

Oz'wraticml y Presuming that tank 22 contains'a quantity of liquid fuel,a measurement is made of the amount of thatfuel in'terms of its depth inthe tankv in the following manner. l Knob 48 ispulled outwardly to thefullest extent- During this, in-f ternal spring 52 is compressed and airis forced into the chamber 44 through aperture 50. When knob 48 isreleased, spring 52 expands to Vdrive piston 45 toward the positionof'Figure 2. v After piston 45 in its movement to the right in Figuresetting after all connections are made. y .Todo

2 has passed aperture 50,1`the entrapped air yin front of it in chamber44 is compressed and compressed air. passes through bore 53 into out letchamber 54 from whence it branches into conduits 6| and 2|. L

Initially the high air pressure delivered `to Sylphon 59 `throughconduit 6| quickly expands the Sylphon to its maximum extent and therebyrocks the rocker' assembly to such extent that pointer 38 momentarilyswings up to the full position with respect to scale 29. However, sincethe lower end of tube 9| opens into "the liquid of tank 22, the head ofthe liquid in the tank determines the air pressure that can' belcon-ylined in the otherwise closed air pressure sys-1 tem of tube 8|, conduit2|, chamber 54, conduit 6| and Sylphon 59. VBore 53`is rsealedtightbypiston 45 at this time. Air will therefore escape through opening 92and pass in bubbles -upwardly through the tank liquid until the airpresey sure in that system is balanced by the head of liquid. As airescapes through opening 92, as when the tank is only partiallylled,.pointer 38 will -dropby its own ,weight vuntil when the and thereading on scale 29 is an indication of the 4depth of the fuel in tank22. f

Theabove operation'isiaccomplished in less" than a minute'and itprovides a temporarily:ac-. curate measurement'l off the depth of,liquid in the tank. It remains accurate for several min.-V

utes after which the air usually leaks fromy the n f owner in the caseofthe fuel oil tank ofFigure 14. `It is accomplished by rotation ofvscrew12 to change the position of cradle 42. This does not change the rateofpointer deection.

f Thezero adjustment is particularly usefulin adapting the gauge to topor -bottom connection to the tank. It is ordinarily desirable in boatsto provide the kbottom connection of Figure 14, and the gauge'is usuallyso adjusted whensold to 'the user. However, should the bottom connectionbe undesirable'he may provide the top connection of-Figure 2,.in whichcasehe will findy after the'connectionsyare made that he `must changethe gauge zero setting due to the differ,- ence inl the static heads ofliquid effective in the tanks of Figure 2 and Figure 14, the liquid headbeing greater in the bottom connection of Figure 14. This adjustment is4also vused to locate-.pointer 38 at zero when` panel 26 is inclinedfromthe verti-cal. f y f It is usual to make a second check on the zerothis, partially llthetank with fuel, measure the liquid depth with astick, .operate therknob 48 to obtain a scale reading and compare they,reading rwith the stick measurement. If they do not agree, rotatescrew '|2unti1 the reading of scale 29 corresponds with the stickreading. Thegauge is now accurately installed and ready for use atanytime. vThe relatively` delicate pointerrate deflection adjustment ismade at the factory an-d since a gauge is available for each rtype oftankr and the tanks of each type are of uniformfdimensions,v thisadjustment usually need not be disturbed.lr It can bechecked bymaking aseries of readings on the gauge with different amounts of fuel in thetank. v .n v

If the boat contains more than one tank, each tank may be selectivelyconnected to the `gauge by -a suitable two way valve in conduit 2|.

K The gauge illustrated in Figures 12-19 is par-' ticularly ,adapted tohome type fuel oil tank intrated. A scale idial 9D is secured to anupright tab 'on'frame 93 behind window 95.

Sylphon support 52 is secured as by set `screw 63 in a; bracket 96 rigidwith the instrument frame and cylinder 9T. Screws 98 attach bracket 96to cylinder 91, and cylinder 91 is attached `to Y frame 93 asby screws|00. The interior of cylinder 941 is ythe same as that of cylinder 43.At

the rear of cylinder 91, however, bore 53 opens' into a transversechamber 99 in which is soldered one end of a tube |I thatV is bentrearwardly to pass through slot |02 in frame 93 and provide a terminal|03 for attachment of a conduit |04 leading to a tting at the bottom ofa fuel oil tank |06. A conduit |01 connects tube |0| to the interior ofSylphon 59'. I

Cradle 42 is pivotally mounted on shaft 68 as in the previouslydescribed embodiment, and set screw 12 threaded in a frame lug |08 atthestop of the gauge bears against the bridge of cradle 42 to providethe zero adjustment of the gauge.

A pointer |09 coacting with scale 90 is secured to a rocker assembly(Figure l5) and pivotally supported at opposite'ends on cradle 42 inpivot screws 83 and 81 as in the other embodiment. The axes of screws 83and' 81 are parallel and aligned. Locknuts ||2 are provided on the pivotscrews. A counter-weight I I3 is secured to pointer and rocker assemblyto tend' to urge the pointer toward the empty indication of scale 98.

Referring to Figures -19, rocker assembly'l I preferably comprises arectangular bar I|4 of brass or some other malleable metal which'retainsa given shape. Bar I|4 is formed at opposite ends with conical bearingsurfaces |I5 and |||i that have parallel axes displaced 0.02 inch, onebeing on the central axis of bar |I4, for mounting the bar on pivots 83and 81.

As illustrated in Figure 17, bar I |4 is apertured at IIT to accommodatea rivet |I8 for securing together the upper end of pointer |09, acounterweight ||3 and bar II4. Bar IIII is notched at ||9 to provide aweakened portion |2| eccentric to the aligned axes of bearings ||5 and||6 and which may be twisted to enable the opposite ends of the bar ||4to be relatively rotated for shifting the fulcrum axis of pointer |09relative to pivot |23 to change the distance therebetween and accomplisha rate adjustment similar to that of Figures 1-11.

A slot |22 is milled into one side of bar I I4, and a wire pin |23 isinserted and crimped into the slot to provide a pivot connection for theend of link 64 as illustrated in Figure l5. The end of pin |23 is bentover into aperture |20 to prevent accidental removal during operation.

In operation the gauge of Figures 12-19 is the same as that of Figures1-11, except that counterweight |I3 serves to restore the pointer tozero. The zero adjustment for bottom connected tanks is checked asabove. The pointer rate of deflection adjustment is made by holding thelong portion of bar |I4 stationary with a wrench and applying a secondwrench to the short eccentrically mounted portion and turning it,thereby twisting and deforming weakened portion |2| and shifting theactual fulcrum axis of rocker assembly with respect to the axis linkpivot |23 to change the degree of rocking of assembly I for a givenstroke of link 64.

I have provided a simple and useful pressure gauge for measuring theamount of liquid in tanks or the like. In these gauges above described,I may obtain motion magniiications between the Sylphon and pointer endof up to 100 to 1, utilizing only a single lever and no multiplicationgears. This gives excellent accuracy with a minimum of friction. The twobasic adjustments are novel subcombinations of use in any apparatus andare separate and independent. The pointer deiiection rate adjustmentchanges the fulcrum axis of the rocker assembly lever,

andthe-zero adjustment shifts the entire linkage with respect to thebellows and scale without disturbing the -deiiection adjustment. Thegauge may be installed with ease and accuracy by any purchaser, and itis usually necessary to make only the simple zero adjustment oninstallation.

The rocker construction and adjustments and other features of the abovetwo embodiments may be interchanged at will without departing from thespirit of the invention. The adjustment of Figure '15 less expensive,but the adjustment of Figure 4 is more', accurate and preferable formore expensive gauges. f

The invention may be embodied in other specic forms without departingfrom the spirit or essential characteristics thereof. The presentembodiment is therefore to be considered in all respects as illustrativeand not restrictive, the scope of the invention being indicated by theappended claims rather than by the foregoing description, and allchanges which come within the meaning and range of equivalency of theclaims are therefore intended to be embraced therein. What is claimedand desired to be secured by United States Letters Patent is: f

1'. In an instrument, a pointer connected rocker member pivotallysupported at opposite ends for rocking o'n al longitudinal axis, saidrocker member comprising two end sections connected by an intermediatesection, and an actuator link pivotally connectedV to one of said endsections on an axis adjacent and slightly inclined with respect to thepivot axis of said rocker member, said intermediate section beingtorsionally adjustable to change the distance between said axes. 2'. Inan instrument, a pointer carrying rocker member pivotally supported atopposite ends on a fixed axis, said rocker member comprisinglongitudinally spaced separate members, a condition responsiveelementpivotally connected to one of said members on an axis spaced fromsaid pivot axis, and means interconnecting said members adjustable toeffect relative transverse displacement of said members for altering thedistance between the axis of rotation of said rocker member and the axisof said connection between said element and said one member.

3. In an instrument, a rocker member pivotally supported on opposedpivots, a condition responsive element pivoted to the rocker member on'an axis spaced from the pivot axis of said rocker, saidrocker membercomprising longitudinally spaced sections having a rotatable eccentricconnection between them adjustable to permit relative transversedisplacement of said spaced sections to alter the distance between saidaxes. .Y 4. In an instrument, a pointer carrying rocker member pivotallysupported at opposite ends, said rocker member comprising longitudinallyspaced sections interconnected by a section that is torsionallyadjustable to effect relative transverse displacement of said spacedsections, and a movable condition responsive element pivoted to saidrocker member on a longitudinal axis that is spaced from the axis ofrotation of said rocker, said torsional adjustment of the rocker memberchanging the distance between said axis of rotation of the rocker memberand said 1ongitudinal axis to vary the action of said element upon saidpointer.

5. In an instrument, an integral rocker bar made of a metal that retainsa given shape, said bar comprising end sections connected by a twistableintermediate section, aligned fixed pivot elements in said instrument,substantially parallel but slightly transversely displaced sockets inthe respective ends of said bar for freely rockably mounting said bar onsaid pivot velements in said instrument, an actuating member pivotallyconnected to one end section of said bar on an axis that issubstantially longitudinal but transversely spaced from the pivot axisof said bar, said spacing determining the effective leverage on saidbar, and a pointer rigid with said one end section of said bar, thedistance between said longitudinal axis and the axis of rocking of saidbar being varied when said end sections are relatively twisted aspermitted by said intermediate section to vary the displacement of saidpointer for a given movement of said actuating member.

6. In the instrument defined in claim 5, said pivot elements beingconical headed and said sockets being conical but of a greater apexangle than said elements to permit free tilt of the rocker axis withsaid adjustment.

7. In an instrument, a pointer carrying rocker member pivotallysupported at opposite ends for rocking about a Vfixed axis, said rockermember comprising longitudinally spaced sections, a condition responsiveelement pivotally connected to one of said sections upon an axis that islaterally spaced from said pivot axis, and means interconnecting saidsections torsionally adjustable to eiect relative transversedisplacement of said sections for altering the distance between the saidaxes and thereby varying the amount of movement of the pointer inresponse to a given movement of said condition responsive element.

8. In the instrument defined in claim 7, a movable member on which saidrocker is pivoted, and means for adjusting said member to displace saidrocker in a direction toward or away from said condition responsiveelement for eifecting zero adjustment of said pointer.

9. In an instrument, a rocker bar made of a material that holds a givenshape after deforma- I tion pivotally supported at opposite ends, apointer having one end rigid With said bar, means for connecting amovable condition responsive element to said bar for rocking it aboutits pivots, and a weakened readily deformable region in said barintermediate said pivoted ends.

10. In an instrument, a rocker bar comprising two longitudinallydisposed members each mounted at its outer end on a stationary pivotmember, and said pivot members having parallel axes, a cylindrical boreyin the inner end of one of said members, and a cylindrical bossprojecting from the other of said members into snug frctional engagementin said bore, the axis of said means, and a` rocker extending betweensaid pivot v means withr eccentrically connected end sections eachmounted on one of said pivot means, means for rotating said rockercomprising'a member rpivoted to said rocker upon a longitudinal axisspaced from the axis of said pivot means, said end sections beingrelatively rotatable at said eccentric connection for changing theinclination of said rocker with respect to said pvot axis and therebychanging the distance betweensaid axis of rotation of the rocker andsaid longitudinal axis to vary the degree of rotation of said rocker fora given stroke of said member.

12. In the instrument defined in claim 11, said aligned pivot meanshaving conical surfaces and said rocker having coacting conical bearingsurfaces at opposite ends journalled on said pivot surfaces, said pivotsurfaces permitting such angularity of the rocker with respect to thealigned axis of the pivot means as may be necessitated by theadjustment.

13. In an instrument, axially aligned pivot means, and a rockerextending between said pivot `means with eccentrically connected endsections each mounted on one of said pivot means, means for rotatingsaid rocker comprising a` member pivoted to said rocker upon alongitudinal axis spaced from the axis of said pivot means, said endsections being relatively displaceable at said eccentric connection forchanging the inclination of said rocker With respect to the pivot axisand thereby changing the distance between said vaxis of rotation oftherocker. and said longitudinal axis to vary the degreel of lrotation ofsaid rocker for a given stroke of said member.

HEINRICH HERMANNY.

References Cited in the file of this patent UNITED STATES PATENTS GreatBritain Dec. 5, 1929

